<template>
    <div id="app">
        <div id="nav">
            <h1>Keep Alive s</h1>
            <p>State: {{ state }}</p>
            <router-link to="/">Home</router-link> |
            <router-link to="/about?id=1">About 1</router-link> |
            <router-link to="/about?id=2">About 2</router-link> |
            <router-link to="/end">End</router-link>
        </div>
        <keep-alive>
            <router-view/>
        </keep-alive>
    </div>
</template>

<script>
export default {
    data() {
        return {
            state: '',
        };
    },

    created() {
        setInterval(() => {
            this.state = window.history.state;
        }, 300);
    },
};
</script>

<style>
#app {
    font-family: 'Avenir', Helvetica, Arial, sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-align: center;
    color: #2c3e50;
}
#nav {
    padding: 30px;
}

#nav a {
    font-weight: bold;
    color: #2c3e50;
}

#nav a.router-link-exact-active {
    color: #42b983;
}
</style>
